SERUM ENZYMES OF LYSOSOMAL ORIGIN AS INDICATORS OF THE METABOLIC CONTROL IN NON-INSULIN-DEPENDENT DIABETICS

Several lysosomal enzymes (β-N-acetyl-D-glucosaminidase, β-D-glucuronidase, α-D-galactosidase, β-D-galactosidase, α-D-glucosidase, β-D-glucosidase, α-L-fucosidase and α-D-mannosidase) were determined in the serum of 54 non-insulin-dependent diabetics with different degrees of metabolic control and without complications and in 18 non-insulin-dependent diabetics with complications. The serum levels of β-N-acetyl-D-glucosaminidase, β-D-glucuronidase, α-D-galactosidase, and α-D-mannosidase were significantly (p<0.01) higher in the diabetics without complications. The levels of β-N-acetyl-D-glucosaminidase and β-D-glucuronidase were inversely proportional to the degree of metabolic control, in a statistically significant manner. Moreover the levels of these enzymes decreased to normal values during a 2-month period of controlled oral hypoglycemic drug-diet therapy resulting in metabolic compensation. The presence of complications was indicated by a further increase of serum β-N-acetyl-D-glucosaminidase and β-D-glucuronidase; however the portion of lysosomal enzyme activities due to complications remained unchanged after controlled therapy aimed at compensating the metabolism. The conclusion is drawn that in non-insulin-dependent diabetics, as already shown for insulin dependent-diabetics, serum lysosomal enzymes, especially β-N-acetyl-D-glucosaminidase and β-D-glucuronidase, are good intraindividual indicators of the metabolic control of the disease.